CFLs are terrible in situations where they are turned on and off frequently. I was taught to turn the lights off when leaving a room, so for me this ends up meaning most of the places in my house, bar the living room and the porch light. If you only have your CFL on for minutes at a time (as opposed to hours) then the highly touted life-span drops to that of an incandescent, if not worse. Furthermore the light output can decrease significantly. The CFLs in our home that have been installed for over a year only turn on initially at about half-brightness - not even enough to read a book - and only come up to "full" brightness after being on for about 10 or 15 minutes. Oh, and even this "full" brightness is noticeably dimmer than when they bulbs were new. Finally, every time you turn on a CFL light anywhere in our (admittedly small) house, in emits enough EM radiation to momentarily screw up our TV reception. Not a huge deal, perhaps, but an annoyance if you're trying to watch a show and the reception goes completely black for a second every time someone switches on a light.I'd have to side with green.view on this one. CFLs are definitely not recommended.

I like that someone mentions that the greenest thing you can do is limit your offspring.I just got done reading Thomas Friedman's "Hot, Flat, and Crowded" which I recommend to any one concerned about the environment. One of his main tenets is that people think they will save the environment with trivial changes such as recycling and using those light bulbs. He says that avoiding climate change will take some hard work by society and pretending it won't is a big lie.I did not know that those bulbs contained mercury. Guess I will have to make room in my battery disposal bin for them now.

I read something last year, possibly in the Economist, but I think elsewhere, that pointed out that, depending on what one derives one's calories from, driving may be less CO2 intensive than walking (vegetarians are more efficient than an average car, hard-core meat eaters less so).

Presumably, the column is right though, in that those resolving to walk more are likely to go about reducing their consumption of (at least red) meat.

Moreover, to my mind CO2 produced by renewables is not a problem, as that CO2 will be recaptured by the next generation of soy beans or cattle feed, as the case may be. The same is technically true of fossil fuels, but the timelines are obviously radically different.

Were more than 20 minutes spent on this column? This sequence of drive-by tut-tut-ing was neither helpful nor entertaining. It suggests all of the polish and cohesion of a Twitter feed while lacking any wittiness behind the snark. Please make a resolution to try harder. Thanks and happy new year.

After reading this post I have serious doubts about the correspondents technical qualifications to run a green post. CFLs operate with ~20% efficiency; incandescent bulbs ~5%. In america 1/2 of electricty is generated from coal plants (~40% efficient) and distributed with 90% efficiency. burning one tonne of coal results in 5700lbs of CO2. Assuming a typical light is on for eight hours a day, SWITCHING OUT AN INCANDESCENT FOR A CFL RESULTS IN 504LBS OF CO2 NOT EMITTED!your corrsponent clearly does not understand that the energy associated with manufacturing the CFL is trivial compared to the energy used during operation making the lifetime irrelevant. The mud slinging at wind subsidies is similarly missinformed. The corresponent suggests that subsidies are geographic in nature and will result in wind turbines going up in places that are not windy. The wind subsidy is a FEDERAL PRODUCTION TAX CREDIT. it has no geographic component. Roughly 90% of wind capacity installed in '08 was in texas and oklahama precisely b/c that is where the high wind is and the PTC makes it profitable to install only in high wind areas. Can the Economist not find an engineer who understands Green Tech to run this post?